This invention relates to a current switching device for a motor and more particularly to an improved control for a reversible DC electric motor.
Direct current electrical motors that offer reversible operation are used for a wide variety of purposes. For example, such motors are employed frequently in marine propulsion devices for driving a reversible fluid pump to operate the tilt and trim mechanism of the outboard drive. As such, the electric motor is selectively energized from a battery for rotation in either forward or reverse direction to raise or lower the outboard drive. Normally, fairly high current loadings are transmitted and it has been the practice to employ a pair of three contact electrical relays for controlling the circuitry between the battery and the electric motor in response to the operator controlled switch. However, such electrical devices as three contact relays are quite expensive when transmitting such high powers.
It is, therefore, a principal object of this invention to provide an improved high capacity switching device for a reversible electric motor that permits the use of relatively low cost electrical components.
It is a further object of this invention to provide an improved simplified and low cost arrangement for switching an electric motor between forward and reverse operation.
It is a further object of this invention to provide an improved low cost switching device for a reversible fluid pump for an outboard drive tilt and trim unit.